1. Field of the Invention
The invention relates to a process and a circuit arrangement for the automatic recognition of signal sequences such as speech and/or music signals, in particular for the statistical evaluation of the frequency of play of music titles, commercial advertising spots, or verbal materials.
2. Description of the Prior Art
For various purposes, such as keeping track of royalties for creators of music works, monitoring whether certain commercial advertising spots are being played by radio stations, etc., it is necessary to determine whether certain signal sequences coincide with each other.
Heretofore, this work has been accomplished by having a large number of persons listen continuously to various radio stations to determine whether certain music titles, commercial advertising spots, verbal materials, etc. are played. This method results in high personnel costs and it is not sufficiently reliable due to human error, inattentiveness, etc.
Therefore, the primary object of the present invention is to automate this process by providing a method of and a circuit arrangement for the automatic recognition of signal sequences. The word "recognition" as used herein relates to unique entities. Thus, the objective is only to recognize whether an individual, unique piece of music is present or not. It is not an object of the invention to determine to degree of similarity between two signal sequences as is the case with automatic speech recognition. In automatic speech recognition (cf. West German OS No. 23 47 738), the object is to obtain a semantically oriented set of characteristics that can be used to recognize that the same words are identical when spoken differently and, if possible, even when spoken by different persons. According to the present invention, however, even minor differences in signals, even though semantically identical or at least quite similar, should cause rejection as an "unfamiliar" signal.